Apparatus for agitating slurry, etc.



July 6 n 1,591,915 P. T. LJNDHARD APPARATUS FOR AGN/WING sLURRY, ETC

Filed AuguSC 4, 4 Sheets-Sheet 1 @wom/ttor @Ml TUM/Mz @1Mo/mago @aan July 6 1926. l

P. T. LINDHARD APRARATUS Fon AGITATING sLURRY, E'rc Filed August 4, 1924 4 Sheets-Sheet 2 WIW! July 6 ,1926. l 1,591,915

P. T. LINDHARD APFARATUS Fon AGITATING sLunRY, ETC

Filedugust 4, 1924 4 sheetsheet 5 -nvewtoz @QQMM July 5 926.

F. T. LBNDHARD APPARATUS FOR AGITA TING SLURRY, ETC

4 Sheets-Sheet 4 Filed Augusi 4, 1924 milll @nue/nto@ Patented July Y6, 1926.

A UNITED STATES PATENT OFFICE.

EOVL T. LINDHARD, OF BROOKLYN, NEW YORK, ASSIGNOR TO F. L. SMIDTH & CO., 0F NEW YORK, N. Y., A CORPORATION 0F NEW JERSEY. i

APPARATUS FOR AGITATING SLURBY, ETC. I

In certain industrial processes there are employed, at one stage or another, semiliquid masses of material which consist of solid particles suspended in liquid and must be agitated constantly in order that the uniformity of the mixture shall be maintained. In the manufacture of Portland cement by the wet process, for example, the slurry, consisting of finely ground Portland cement raw materials and water, must be agitated constantly in order to prevent the 'solid particles from being precipitated. This agitation is commonly carried on in tanks or vessels -o-f relatively small capacity, either by means of air injected under pressure at the bottom of the mass or by mechanical agitators which consist ordinarily of vertical shafts mounted to rotate in fixed bearings and provided with horizontal arms, or sometimes by a combination of air and a mechanical agitator. The use of Yair under pressure, either by itself or in conjunction with a mechanical agitator, is not always satisfactory because the air is apt to move, either from fixed nozzles or from nozzles mounted on a mechanical agitator, in

lines or paths which are more or less defined and therefore fails to agitate thoroughly the entire mass. The use of mechanical `agitators iny relatively small tanks involves considerable expense in the construction of many tanks, the equipment of many tanks with the agitating devices, and the consumption of power. Y

The present invention has for its object to make it possible. with a single apparatus` to agitate thoroughly the large volume of slurry or like semi-liquid material in a single large tank. In accorda-nce with the invention a single set of mechanical agitating devices, the action of which is supplemented if desired by air under pressure, is supported bv a carrier which during the operation of the agitating devices is moved to and fro upon an elongated tank, by means which,

preferably, are controlled automatically so that the movement of the agitating devices continues as long as may be desired. By

such means the entire mass may be agitated.`

sufficiently to prevent precipitation of the solid particles. Details of construction of practical embodiments of the invention will be fully explained hereinafter with reference to the accompanying dra-wings in whichf- Application led August 4, 1 924. Serial No. 729,944.

Figure l is a view in elevation of one form of agitating device embodying the invention in position with respect to a tank which is shown in transverse section.

Figure la is a diagrammatic view of the electrical connections of one of the motors shown in Figure 1.

Figure 2 is a top view of the mechanism shown in Figure l, with the platform partly broken away to show parts below.

Figure 3 isy a detail view of the carrier and its operating means as seen in elevation from the left hand in Figure 2.

Figure 4 is a detail view in longitudinal section and on a larger scale of the drum shown in Figures 1 and 2.

Figure 5 is a view of the drum in end elevation. l

Figure 6 is a detail viewrillustrating the means for maintaining proper tension on the electric cable.y v

Figure 7 is a top view illustrating a modified form ofthe means for effecting movement of the carrier.

Figure 8 is a view in end elevation of the parts shown in Figure 7. f

Figure 9 is a view of the same parts in elevation as seen from the point of view at right angles to that of Figure 8.

Figure 10 is a sectional detail view, on a larger scale7 showing means for securing the cables to the sheave.

In the embodiment of the invention chosen for illustration in Figure 1, with details shown in Figures 2-6, the tank which is to receive the semi-liquid mass and may Vbe of any suitable length, is shown as having side walls a, a, and a bottom a', with rails a2 extended longitudinally on the side walls a, the end walls not being shown.

Resting upon the rails a2, so as to be movable to and fro over the tank, is a carrier b, which may comprise girders b', cross girders b2, and a platform or iioor b3. The carrier is supported upon the rails a2 by fianged wheels c on shafts 0 which may be driven through sprocket chains 02 from a shaft c3.

which is mounted in suitable bearings on the i d of ordinary construction connected to rela)v ope-rated reversing'switches fl for controlling the direction of rotation ot the motor ci', so that as the carrier reaches one end or the other of its travel, the corresponding limiti switcli'. b v Contact with a stop (Z2, shall be shifted so 'as' toeffect' reversal of the motor and therefore areversal of the direction ot travel ofthe carrier.

The motor c5 may be supplied with eurrent by an)v convenient means from an)v suitable source;indicated at (I3 in'Figure 1.

. Suspended from the carrier 7) is a suitable frame which ma)7 comprise vertical members e, a bottom member c', and braces e2. Also depending below theI carrier there are, in the construction illustrated, two vertical shafts f and f which carry cross arms f2. In the construction` shown the cross arms ot the two shatts are in the same plane and' the two shai'ts are therefore' rotatedl in opposite directions with' their respective cross arms eet' at .right angles. At the lower end oli' each shaft` below the 'trame member c', is a cro'sisarm 7', one part;f ot which is equipped with scrapers f4 suspended from the cross arm so that they just touch the bottom ol the tank and agit'ate the' material at the bottom.

As a convenient means for rotating the agitating` device eaeh'slia'tt may have at its upper end. above the platformF or floor of the carrier a bevel gear f5 which is engaged b v a= correspondingv bevel pinion f/ onl a shaft g. supported in suitable bearings on the carrier andv driven continuously in one direction by a motor g2 through a suitable speed reduction device indicated at Means lor deliveringr air under pressure into the mass ot' slurry,'nea-r the bottom of the tank, are pretera-fbly combinedwith themechanical agritatilng devices. Inv the construction shown an air line L, to which air under pressure may bei supplied b v anv convenient means or as hereinafter described, is connected th'i'ouah a branch /zf and a suitable sluiting' box'l with an air channel 7e? in the upper portion oi each shaft f, from'r which, b v af pipe 7a3 carried down along. the shaft, f and outwardly aloner the arm f, air iS c011- ducted to a nozzle 7b4 through which air is d isrha-reed in-to the mass ot' slurry.

nfv convenient means may be provided l'or supplying" elect-ric current to the motor 'f/2 and for supplyingr air under pressure to' the air line 7L, but in order that such means may function satisfactorily during. the reciprocations ot the carriage and the movement ot' the agitators through the slurry, such means as are shown in Figures l-G of the drawings and, in slightly modified' form, in Figures T-O.- may be en'iployed.V In the construction illustrated in Figures 1-6 the win-ding drum rf, preferablyv formed with a helical groove', is mounted at one end of the carrier on a hollow sha-'ft which is supported in suitable bearings. This hollow shaft. which is closed at one end, is connected at the other end, through a stuflinIfjr box 2, willi the air line /z/ and at a convenient point is provided with a branch L"l which is carried through the shell of the drulnand is connected to an air hose L" which is carried to one end of the tank and is there connected to any convenient source ot' air under pressure. An electrical cable T i, connected at the opl'imfzitecnd of the tank to a suitable source of supply, is connected to the drunii 1', at the end ot' the'drum opposite to that atv which the air hose is conllectcdafandis carried within'the drum where the wires ot the cable are connected to slip rings i Vtrom which connection is made, as b v wires 7, to the motor (/f in a manner well understood and not requiring detailed cxplanation. lt' will be understodthat in the travel ol" the carrier to and tro over the tank the aii'l hose and the electric cable will be wound upon and given ofl from the drum i, the one'beincr wound on the drum as the other is gi'vcnotl'. ln: order that proper tenision may be maintained on the hose and cable, it is desiralile thatv a tension device lic applied to' one or the other. As shown in Figure (3, a weight 3 mayY be connected' by a cord i9, whichk passes over a shcavc 10, to a W strain insulator 1f which is secured to the cable 5. In' this manner, during the travel of the carrier and the movement of the agitat-ing devices to' and 'tro through the tank,

the electric current is supplied to the motor m0 (/l for operatingr the' mechanical agitators andair under pressure issuppliedf to the air line and thence to theA air nozzles on the agi'- tators.

The construction' shown in Figures 7, 8', '9 105 and 10 is the same als that already described' eficcpt'with respect to the means `for malntainingr tension on the electric cable i". I n this instance the cable is attached' in one groove oit a doublc-grooved sheave k the 110 sha'tt 7c of which' is suitably supported in bearings-I 71:2 so that the sliea'vcj stands over a pit 7c3. The electricV cableis carried along one ol the arms of the sheave, as at ,'aiid is then connected through the hollow shaft Z7 115 to the switch bo'\v im.' In'the other groove of the'sheave 7c is connected, b v suitable clamping devices shown at Zr* in Figure it), a' wire cable r" to which', in' the pit' 71:", is secured' a counter-weight cG, whereby proper tension l is maintained on the electric cable, 1f and, through the drinn z', on the air hose fi. The tension devices justY described as well as the tension' device shown in' Figure 6,' also serve as means toY compensate for the different l diameters ot the air hose andthe electric cable. B v reason of the difference in diameters a. greater or less length of the cable or the hof-e will' be reeled' on or oilD of the drum z' in the movement of the carrier and such l.

variation in length will be compensated for by movement up or down of the counterweight 8 or las as the case may be.

In operation the carrier is preferably arranged to travel to and fro at a comparatively low speed, as from three feet to tive feet per minute, whereas thc agitating devices may be rotated at a vspeed of perhaps tive to eight revolutions per minute, so that the agitating devices will make a comparatively large number of revolutions during each movement of the carrier in one direction and thereby the scrapers f4 on the lowermost arms of the agitating devices will sweep every portion of the bottom of the tank during each movement of the carrier and the air nozzles h4 of the two agitating devices will describe continuous interlocking curves causing the air to bubble through the entire body of slurry. lihe upward movement of the air causes a gradual displacement of the slurry from the bottom to the top and a very intimate mixing of the slurry is effected through the conjoint action of the air and the mechanical agitating devices and the chemical analysis of the slurry becomes unit'orm and the percentage of water remains the same in all parts of the tank.

It will be understood that various changes in details ot construction and arrangement can be made to suit different conditions of use and that, except as pointed out in the claims, the invention is not to be restricted to the particular construction shown and described herein.

I claim as my invention:

l. Apparatus for agitating slurry, etc., in a tank, comprising a carrier adapted to travel to and fro above the tank, an agitating device suspended from the carrier within the tank, means to eliect the movement of the carrier, an electricmotor and operating connections mounted on the carrier to operate the agitating device, a drum mounted on the carrier, an electric cable having one end connected to a fixed point at one end of the tank and having the other end mechanically connected to the drum and electrically connected to the motor, and a second cable having one end connected to a lixed point at the other end of the tank and its other end mechanically connected to the drum, whereby the electric cable is reeled on and oi the drum as the carrier moves to and fro. Y

2. Apparatus for agitating slurry, etc., in a tank, comprising a carrier adapted to travel to and fro above the tank, an agitating device suspended from the carrier within the tank, means to eifect the movement of the carrier, an electric motor and operating connections. mounted on the carrier to operate the agitating device, a drum mounted on the carrier, an electric cable having one end connected to a ixed point at one end of the tank and havingthe other end mechanically connected to the drum and electrically connected to the motor, and a second cable having Vone end connected to a fixed point at the other end oi' the tank and its other end mechanically connected to the drum, whereby the electric cable is reeled on and oli the drum as the carrier moves to and fro, and means to maintain the electric cable under tension during the movement of the carrier. V

. 3. Apparatus for agitating slurry, etc., 1n a tank, comprising a carrier adapted to travel to and fro above the tank, an agitating device suspended from the carrier within the tank, means to eliect movement of the carrier, an electric motor and operating connections mounted on the carrier to operate the agitating device, a drum mounted on the carrier, an electric cable having one end connected to a xed point at one end of the tank and having the other end mechanically connected to the drum and electrically connected to the motor, and a second cable having one end connected to a fixed point at the other end of the tank and its other end mechanically connected to the drum, whereby the electric cable is reeled on and oli the drum as the carrier moves to and fro, and a counter-balance Weight operatively connected to one of the cables to maintain the same under tension during the movement of the carrier.

4. Apparatus for agitating slurry, etc., in a'tank, comprising a carrier adapted to travel above the tank, a mechanical agitating device suspended on the carrier within the tank, means to effect the movement of the carrier, means to operate the mechanical agitating device, an air line supported on the carrier, an air nozzle on the agitating device and connected to the air line, and means to supply air under pressure to the air line.

5. Apparatus for agitating slurry, etc., in a tank, comprising a carrier adapted to travel above the tank, a mechanical agitating device suspended on the carrier within the tank, means to eli'ect the movement of the carrier, means to operate the mechanical agitating device, an air line supported on the carrier, an air nozzle on the agitating device and connected to the air line, a drum mountedon the carrier, an air hose having one end connected to a fixed point at one end of the tank and having its other end mechanically connected to the drum, .an air connection through the drum Jfrom the hose to the air line, and a second cable having one end connected to a fixed point at the other end of the tank and the other end mechanically connected to the drum.

6. Apparatus for agitating slurry, etc., in a tank, comprising a carrier adapted to travelabove the tank, a frame extending from the carrier downwardly into the tank towarcl but not to. the bottom thereof, a vertical shalt. mounted in bearings inthe carrier and' in the lower men'lber oli' the frame7 arms carried by the shaft between the carrier and the lower member of the frame, other arms carried by the shaft below the lower member ol thev frame and immediately above the bottom of the tank in position to agitato the materialv incontaot with the bottom tank, such shaft and arms constitu-ting a mechanical agitatingr device, means to operate the mechanical agitatng device, and means to elleet the movement of the carrier.

This specilicationsigned this lst day of August, A. D. 1924.

POVL T. LINDHARD. 

